Volume Effect of Real Estate Asset in Korea

HyunWook Ryu,SangSu Keum 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.4

The informational role of trading volume has long been a subject in financial market. In stock market and/or derivatives market, for instance, the issue remains whether the market is efficient; meaning that information(s) from the past is delivered sequentially to the following trades, thus reflected in price. The purpose of this study is to attempt to test the relationship between the price index and trading volume in the housing market to see if the empirical findings could show any change in each other. Vector Auto Regressive model is used to analyze the endogenous variables. Empirical evidence presented in this study shows that trading volume a month before causes change in price index. It is inferred that housing volume traded could relay significant information to the trading process of housing asset.

Business Model Change in Asset Management

HyunWook Ryu(류현욱) 한국산학기술학회 2017 한국산학기술학회논문지 Vol.18 No.9

금융서비스의 한 부분으로 꼽히는 자산관리(Private banking)는 고액자산가(HNWI)를 대상으로 하는 투자자문업이다. 국내 자산관리서비스는 성장을 앞두고 있으나 평가체계 등 구조적 한계 등이 극복할 과제로 남아있다. 아·태지역을 필두로 전 세계적으로 해당시장의 규모가 확대되고 있는 자산관리서비스는 저성장 저금리 환경이 고착화됨에 따라 국내에서도 수요가 급증하고 있다. 다만 고령화에 따른 대고객 관계의 장기화와 각종 규제 등은 보수체계를 압박하는 요인으로 꼽히는 가운데 국내 기업들의 경쟁력 강화가 필요한 시점이다. 본 논문은 service quality model과 관련한 선행연구에서 DEMATEL 모형을 고찰하고 전문가 인터뷰를 통해 Business model elements를 도출했다. 모듈식 자문서비스, 고객에 대한 정교하고 세련된 서비스, 부유층이 만족하는 투자전문성 및 투명성 제고 등을 도출했다. 상대적으로 높은 수익률을 제공하는 해외자산과 낮은 상관관계를 가진 대체투자자산에 대한 관심이 증대되는 여건 속에서 해당분야로의 본 연구는 시의적절한 부분을 연구의 기여로 볼 수 있으며 실증분석을 통한 검증은 연구의 한계로 후속과제에서 다룰 예정이다. Private banking, which is a part of the financial services industry, is an investment advisory business targeting high-net-worth individuals (HNWIs). The demand for asset management services, which isexpanding in the world market as well as in the Asia-Pacific region, is rapidly increasing in Korea as the low-growth, low-interest environment has stabilized. In Korea, the private banking business is ahead of growth, and the evaluation and compensation system of playing institutions remains a challenge. While the aging of the population increases the demand for services, the increasing competition and regulations have decreased the profit margins in the industry. In this paper, a business model is derived from a professional service quality model. Modular advisory services, value-proposition through sophisticated services, and investment expertise with increased clarity would help wealth management firms pursue their opportunities. By interviewing the experts of wealth management banks, this study constructsa business model with elements derived from a relevant literature review. The contribution of this research is to enable these institutions to understand the key factors affecting their financial performances, in order to improve them. This study is limited by one of the research models, and it will be necessary to conduct an empirical test in the future.

Variation of Anthocyanin Content and Bulb Size in Onion (Allium cepa L.) Accessions

Hyunwook Ryu,Hye-Eun Lee,Jiwon Han,Jundae Lee 한국원예학회 2020 한국원예학회 학술발표요지 Vol.2020 No.11

실물자산시장에서의 정보효과에 관한 연구

류현욱(Ryu, HyunWook) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.11

본 연구는 금융투자시장에서 적극적으로 연구되는 정보효과에 대한 동태적 분석을 시도하였다. 기존문헌(들)을 통해 정보거래가 갖는 효과에 대해 고찰하였으며, 국내 아파트시장을 대상으로 실증분석하였다. 자료는 국토해양부에서 공개하는 실거래 자료가 사용되었으며, 2006년부터 2015년까지의 월별 아파트 Data를 EGARCH 분석모형에 적용하였다. 추정한 결과, 전기 거래량이 주택가격의 변동성에 영향을 미치고 있는 것으로 확인한 바, 주택거래량이 전달하는 정보효과(information role)가 금융투자시장과 유사하게 나타날 수 있음을 확인하였다. This study examines the dynamic relations between housing price and trading volume in a set of apartment markets in Republic of Korea to explore the informational role of trading volume in predicting the price volatility. Using monthly index data, EGARCH model is utilized to test for volume effect. To estimate the EGARCH-based volatility, two different sets of region are applied for the monthly return. Strong evidence has been found towards housing turnover leading price volatility, this supports previous studies on financial sector(s). These findings also support that trading volume in the housing market contains information on investor sentiment which, in turn, has a valuation effect on the price.

A Study on Dynamic Relation between Fund Flows and Returns

류현욱(Ryu HyunWook),장용운(Jang Yong Woon) 글로벌경영학회 2016 글로벌경영학회지 Vol.13 No.4

Although the U.S. Federal Government decided to hold the base rate for the month of June, 2016, equity funds have experienced capital outflows due to Brexit uncertainties. In the generality of cases, timing of U.S. interest rate change and major commodities’ value are an important drivers of capital inflows; but, in the real world, the flows have reacted more to one over the others. Thus, it is meaningful to conduct a fundamental approach between key variables, in other words, finding primary drivers. The discussion under which capital inflows and/or returns are controled has been effective in practice. We derive a VAR approach to the dynamic relationship between fund flows and fund returns for the daily sample data from June of 2015 to August of 2016. The results show capital flows are followed by fund returns at statistically significant levels. As with the policy-makers, concentrating more on products and/or product-makers would be more effective concerning capital flows. An example is providing tax incentives since test results show that the higher the returns, the more the money flows into the financial markets. 아직은 발전단계에 있는 국내 펀드는 다양한 형태로 상품화 될 수 있으며 각각의 특성에 따라 투자자의 이해를 구분지어 살펴볼 수 있다. 펀드의 수익률은 투자자의 반응에 따라 달라질 수 있다는 것이 오랜기간 학계의 관심을 끌었으며, 반응의 결과값인 현금흐름(capital inflow)으로 나타날 수 있다는 것이다. 다만 두 변수가 내생성(endogenous)을 보임으로 상호 영향관계를 속단하기 어려운 측면이 있다. 본 연구는 국내에서 판매되고 있는 펀드상품의 일부를 분석하고 투자자들의 관점에서 직접적인 요인을 분석하기 위해 시계열 모형을 설정하여 살펴보았다. 핵심변수 간의 내생관계를 고려하여 VAR 모형으로 분석한 결과, 성과가 높은 펀드에서 수익률이 펀드유입에 선행한 것으로 나타났다. 이는 피드백효과로 해석하는데 한계가 있으나 투자시장에서 펀드수익률이 자본이동의 핵심요인이 될 수 있음을 확인하였다. 2008년 금융위기 이후 변동성이 확대되고 불확실성이 증대된 금융시장으로 안정적인 자금유입을 강화하기 위해서는 요인분석이 필요한 바, 수익률로의 기제를 확인하고, 나아가 금융시장활성화에 기여했다는 점에서 본 연구의 의미를 찾을 수 있다. 다만, 장기적 안정성 검토 등 분석모형에 대한 추가검토 및 세제변수 등 외생변수의 투입을 통한 얻을 수 있는 세밀한 해석은 추후과제로 넘기도록 한다.

나노여과를 이용한 지하수의 미네랄 제어 특성 및 공정 모델링

유현욱 ( Hyunwook Ryu ),김수한 ( Suhan Kim ),김재범 ( Jaebum Kim ),박성혁 ( Sung Hyuk Park ) 한국수처리학회 2016 한국수처리학회지 Vol.24 No.6

This study was motivated to produce healthful and good-tasting water using Jeju groundwater which contains useful mineral ions. The K-index was applied to assess the quality of treated water. The original value of K-index of raw groundwater was -13.3 and nano-filtration process was applied to increase it up to 2.0 with high recovery ratio. The process was tested while circulating the concentrate to a raw water tank for the purpose of increasing mineral concentrations such as calcium, magnesium and vanadium. Among four kinds of membranes tested with different pressure conditions, the membrane with the lower salt rejection ratio at lower pressure condition was favourable for that purpose. The recovery ratio of produced water increased up to 87.5% while circulating the concentrate and water qualities were analyzed at several recovery ratio points. And a mathematical model was used to simulate the higher recovery conditions and then water qualities. When a NE4040-40 membrane was used at 2 bar of pressure, ion concentrations of the concentrate water were calculated by the model. When the system reached 99% recovery, the concentrated water was 20 times diluted with pure water. Then the K-index value reached 2.0 applying the dilution factor.

적색 양파에서 안토시아닌 함량 조절 양적형질유전자좌와 연관된 SNP 분자표지 개발

류현욱(Hyunwook Ryu),김성길(Sunggil Kim),이혜은(Hye-Eun Lee),한지원(JiWon Han),이준대(Jundae Lee) 한국육종학회 2021 한국육종학회지 Vol.53 No.2

The bulb onion (Allium cepa L.), one of the most important vegetables worldwide, contains various functional compounds suchas quercetin, allicin, and flavonoids. Red onions are rich in anthocyanins, a flavonoid that is a functional phytochemical with antioxidativeand anticancer activities. In the previous study, two quantitative trait loci (QTLs) (qAC4.1 and qAC4.2) controlling the anthocyanin contentwere identified on chromosome 4 in an F2 population derived from a cross between A. cepa ‘SP3B’ and ‘H6’. In this study, we developedsingle nucleotide polymorphism-based high-resolution melting (HRM) markers linked to QTLs qAC4.1 and qAC4.2. In addition, we constructeda new genetic linkage map of chromosome 4 using HRM markers and performed a QTL analysis. The QTL qAC4.1 was false, while qAC4.2was a major QTL. The QTL peak position, logarithm of the odds value, and phenotypic variance explained of qAC4.2 was 53.6 cM, 7.45, and 22.51%,respectively. Four HRM markers (AC4.2_65336.1_1123-HRM, AC4.2_53230.3_454-HRM, AC4.2_11999.1_756-HRM, and AC4.2_14596.1_345-HRM)within the QTL region of qAC4.2 were developed in this study. The average anthocyanin content of B (homozygous paternal) genotypes washigher than that of A (homozygous maternal) and H (heterozygous) genotypes for all markers. Consequently, these markers will be useful formarker-assisted selection to develop onion cultivars with high anthocyanin content.

A population-based approach indicates an overall higher patient mortality with peritoneal dialysis compared to hemodialysis in Korea

Kim, Hyunwook,Kim, Kyoung Hoon,Park, Kisoo,Kang, Shin-Wook,Yoo, Tae-Hyun,Ahn, Song Vogue,Ahn, Hyeong Sik,Hann, Hoo Jae,Lee, Shina,Ryu, Jung-Hwa,Kim, Seung-Jung,Kang, Duk-Hee,Choi, Kyu Bok,Ryu, Dong-Ry Springer-Verlag 2014 Kidney international Vol.86 No.5

To date, only a few large-scale studies have measured the effect of dialysis modality on mortality in Asian populations. Here, we sought to compare survival between incident hemodialysis (HD) and peritoneal dialysis (PD) patients using the Korean Health Insurance Review & Assessment Service database. This enabled us to perform a population-based complete survey that included 32,280 incident dialysis patients and followed them for a median of 26.5 months. To reduce biases due to nonrandomization, we first matched 7049 patient pairs with similar propensity scores. Using the log-rank test, we found the mortality rate in PD patients was significantly higher than that in HD patients. Subsequent subgroup analyses indicated that in older patients (55 years and older), with the exception of the subgroup of patients with no comorbidities and the subgroup of patients with malignancy, PD was consistently associated with a higher mortality rate. In younger patients (under 55 years), regardless of the covariates, the survival rate of PD patients was comparable to that of HD patients. Thus, while the overall mortality rate was higher in incident PD patients, mortality rates of some incident PD and HD patients were comparable in Korea.

A prime determinant in selecting dialysis modality: peritoneal dialysis patient survival

( Hyunwook Kim ),( Dong-ryeol Ryu ) 대한신장학회 2017 Kidney Research and Clinical Practice Vol.36 No.1

The number of patients with end-stage renal disease (ESRD) has rapidly increased, as has the cost of dialysis. Peritoneal dialysis (PD) is an established treatment for ESRD patients worldwide; it has a variety of advantages, including autonomy and flexibility, as well as economic benefits in many countries compared to hemodialysis (HD). However, the long-term survival rate of PD remains poor. Although direct comparison of survival rate between the dialysis modalities by randomized controlled trials is difficult due to the ethical issues, it has always been a crucial point when deciding which dialysis modality should be recommended to patients. Recently, in many countries, including the United States, Brazil, Spain, Australia, and New Zealand, the survival rate in PD patients has significantly improved. PD patient survival in Korea has also improved, but Korean PD patients are known to have higher risk of mortality and major adverse cardiovascular, cerebrovascular events than HD patients. Herein, we further evaluate why Korean PD patients had worse outcomes; we suggest that special attention should be paid to patients with diabetes, coronary artery disease, or congestive heart failure when they choose PD as the first dialysis modality in order to reduce mortality risk.

분산형 저류시설-하수관망 네트워크 시스템의 입자군집최적화 기반 모델 예측 제어

백현욱(Hyunwook Baek),류재나(Jaena Ryu),김태형(Tea-Hyoung Kim),오재일(Jeill Oh) 한국지능시스템학회 2012 한국지능시스템학회논문지 Vol.22 No.6

도심지역의 하수관거 시스템은 우수 수용능력 및 하수 월류 발생 등의 시스템의 한계점을 가지고 있어, 강우시 우수 유출수로 인한 침수저감과 더불어 도시비점오염원의 저감에 모두 대응할 수 있는 저류시설의 도입이 주목받고 시작하였다. 최근 환경부에서는 방재적 우수관리와 더불어 합류식 하수관거 월류수, 분류식 우수관거 유출수 처리를 포함하는 다기능 저류시설을 “하수저류시설”이라 통칭하고, 이의 도입을 적극 추진하고 있는 실정이다. 반면 대규모 단일 저류시설 설치의 경우에는 공간 확보의 문제가 발생할 수 있으며, 이에 대안으로는 중·소규모의 분산형 저류시설 설치 및 운영을 들 수 있다. 본 연구에서는 분산형 저류시설-하수관망 네트워크 시스템의 최적 운용을 위한 모델 예측 제어기법을 제안한다. 이를 위해 첫째로 네트워크 시스템의 각 구성 요소의 수리모델을 제시함으로써 보다 정밀한 하수관망 네트워크의 거동을 모사하고자 한다. 둘째로 제안된 모델을 기반으로 현재의 강우 유입량을 고려하여 각 저류조의 수위, 하수관로의 유입/유출량을 예측하여, 입자군집 최적화 알고리즘을 이용한 모델 예측 제어기법을 바탕으로 주어진 제약조건을 만족하며 상황을 바탕으로 제안된 제어기법의 사용여부에 따른 효과를 비교 분석하고, 이의 타당성을 검증하고자 한다. Urban sewer systems has a limitation of capacity of rainwater storage and problem of occurrence of untreated sewage, so adopting a storage facility for sewer flooding prevention and urban non-point pollution reduction has a big attention. The Korea Ministry of Environment has recently introduced a new concept of "multi-functional storage facility", which is crucial not only in preventive stormwater management but also in dealing with combined sewer overflow and sanitary sewer discharge, and also has been promoting its adoption. However, reserving a space for a single large-scale storage facility might be difficult especially in urban areas. Thus, decentralized construction of small- and midium-sized storage facilities and its operation have been introduced as an alternative way. In this paper, we propose a model predictive control scheme for an optimized operation of distributed storage facilities and sewer networks. To this aim, we first describe the mathematical model of each component of networks system which enables us to analyze its detailed dynamic behavior. Second, overflow locations and volumes will be predicted based on the developed network model with data on the external inflow occurred at specific locations of the network. MPC scheme based on the introduced particle swarm optimization technique then produces the optimized the gate setting for sewer network flow control, which minimizes sewer flooding and maximizes the potential storage capacity. Finally, the operational efficacy of the proposed control scheme is demonstrated by simulation study with virtual rainstorm event.